Figure 1

CTC enrichment in model system experiments. A) GFP-LNCaP cells mixed with blood from a normal donor were visualized by phase contrast and fluorescence microscopy using a 40× objective. Two fluorescent cells (see arrow) are visible in a background of non-fluorescent blood cells. B) GFP-LNCaP cell (see arrow) after enrichment with anti-EpCAM coated magnetic particles. Captured GFP-LNCaP cells were coated with numerous magnetic particles (non-fluorescent spheres, see arrowheads.) C) Immunomagnetic fraction from similarly processed normal donor blood (without added prostate cancer cells). This fraction is practically devoid of blood cells, with a low amount of non-fluorescent background material (see arrow). Magnetic particles are marked by arrowheads. D) PSA mRNA detection in immunomagnetically enriched C4-2 cells. Normal blood mixed individually in samples that contained 5, 10 and 25 added C4-2 cells were incubated and captured with anti-EpCAM magnetic particles out of 5 mL EDTA-treated blood. Error bars represent one standard deviation of repeat capture experiments (n = 10 for samples that contained 5 or 10 cells), n = 5 for samples that contained 25 cells). E) PSA mRNA copy numbers from immunomagnetically processed blood samples. Bars 1 through 8 represent replicate samples containing LNCaP cells (2 cells/mL, 4 mL total blood volume) that were processed using anti-EpCAM magnetic particles. Bars 9-12 represent control samples. The presence of LNCaP cells, control magnetic particles (devoid of anti-EpCAM primary antibody), or anti-EpCAM magnetic particles is indicated by the +/- symbols.